How Much Does it Cost to Repair a Concrete Foundation?

Concrete Foundation Repair Prices

Signs that your concrete foundation needs to be repaired include bulging floors, doors that are difficult to close, cracks in the foundation and cracked inside and outside walls. Damage to a foundation usually comes in the form of cracks due to water damage which start small and may widen over time. Foundation repairs may also be required due to sinking. This could be caused by soil losing its moisture over time, underground roots that wither and die, earthquakes, flooding due to poor water drainage or poor-quality original construction.

Concrete Foundation Repair Costs

If you sign shows home of foundation problems the first step is determining the cause of the problem. This could involve hiring a structural engineer for around $500 if the damage is bad. It may also be necessary to test the underlying soil. For example, one homeowner suspected their home was on an old garbage dump and that the uneven soil was causing their foundation to settle. Clay in the soil is another frequent cause of foundation settling. Soil testing could cost $500 to $1500. A cheaper option would be to contact local government officials, soil engineers or universities for topographical maps of the area that could tell you what kind of soil you’re dealing with. You may be able to hire a geology student to do it for less.

Basic foundation cracks cost around $500 to $1,000 a piece to repair; it’s a pretty straightforward patching job involving cleaning out the crumbling concrete and inserting caulking. It’s unusual to only have one crack; if you see one there are likely others.

Slabjacking (sometimes also called mudjacking) refers to a process whereby a mix of cement, water and sand is pumped in under the existing concrete which acts to lift the uneven foundation back into proper alignment. An average price for slab jacking is approximately $1,500 to $3,500 depending on the complexity of the job.

Another common approach to foundation is what’s called piling or piering. This involves driving steel pilings 8-10 feet apart into deeper soil to provide support to a sinking foundation. The average cost for foundation piers is around $750 to $1,500 apiece depending on the type of foundation pile, how deep they need to be inserted, and how difficult it is to get below the foundation (is there a lot of hard rock, etc.) Count on approximately 3-6 foundation piles per crack, although this can vary quite a bit.

An extreme form of concrete foundation repair is done by raising the foundation. This is done by lifting a house off of its foundation, excavating the area underneath, building a new foundation or renovating the existing one, and then reinstalling the house on top of the new foundation. It is essentially the way a historic building is moved, only the house is put back in the same spot. This could be done in extreme flood areas or for a house with a completely ruined foundation. You can expect to pay somewhere around $20,000 to $30,000 to raise foundation on an average sized home, although keep in mind it is a very complicated procedure that requires cutting anything that penetrates the sides of the house and goes down to the basement. This includes all electrical and plumbing. If there are complications, the total cost could end up being as much as half the value of the entire home.

How much does a foundation drainage system cost?

One way to prevent excessive water absorption in the soil under your home’s foundation, which could lead to settling, is to install a good foundation drainage system. This can include systems installed outside the edges of a foundation and also those installed under a foundation.

Foundation drainage tile systems are typically installed in new construction. However, adding basement drainage after the fact could cost $2,500 to $6,000 and up to $10,000 to $12,000 or more in some cases. This high price tag is due to the fact that it involves interior excavation, exterior excavation, or sometimes a combination of the two.

A cheaper option is sump pump drainage. This involves installing an isolated “sump pit” with a complimentary sump pump for around $300 to $800.

Another option is to install a French drain, which involves digging a ditch around the perimeter of a foundation as well as installing sections of perforated pipe under crushed stone or gravel. French drains cost approximately $20 to $30 per linear foot. A reasonable estimate to do a home is $1,000 to $2,000 but could be more depending on the size and soil conditions.

Because a lot of foundation flooding is due to improper water runoff, a cheap solution could be to install new downspout drainage. You can have new downspouts added to an entire house for roughly $400 to $1,200 professionally installed, or a fraction of the cost as a do it yourself project.

You could also pay a landscaper to recontour the slope of your yard and keep water from running into the foundation. Landscaping drainage costs somewhere around $1,500-$2,000.

Tim Carver explains the importance of proper foundation and yard drainage and instructs how to install foundation drain tile on his website, Ask the Builder.com.